It can only be bought for robots and it has a huge chance of failure. I think its cheapness is okay. Maybe if you want more detailed rules, it could be such that for every inch in size it costs 2 cp so a 3" death robot would have to spend 6 cp to get it since it's bigger. Or something like this:

Level Cost:2 cp per chance on a D6...6 only = 2 cp5 and 6 = 4 cpetc, but max is 4 5 and 6

Then multiply that by the size in inches.

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"Each night alone I dream, that I'm a rebel Roller Queen‼I'll be a star that shines, I can make the whole world mine‼"

Level Cost:2 cp per chance on a D6...6 only = 2 cp5 and 6 = 4 cpetc, but max is 4 5 and 6

Then multiply that by the size in inches.

Everything up to the bold highlighted bit is fine. I've faced that kind of stuff before and it isn't so powerful it wrecks the game. The type of units able to use it (robots) should keep the numbers low.

The bold highlighted bit... AC with self repair? How much would that cost for a 4+ I'll be back roll. It would bring it in line with the way Imperial Titans work in Epic.